I had a similar problem with mine, using the molex connector from the PSU to power my touchscreen. The computer kept restarting when it was plugged in. Then I changed the monitor wires to be powered directly from the car power system, and the computer started up just fine. I think the monitor was drawing too much power, and so too might your USB Hub. This is all just based on observations, but see if you can power it another way.

I had a similar problem with mine, using the molex connector from the PSU to power my touchscreen. The computer kept restarting when it was plugged in. Then I changed the monitor wires to be powered directly from the car power system, and the computer started up just fine. I think the monitor was drawing too much power, and so too might your USB Hub. This is all just based on observations, but see if you can power it another way.

If you can't get it from the power supply I'd ditch the psu... I have the M2 ATX also w/ the Jetway C7 25w version in a VoomPC. I'm having issues w/ my USB DAC (crackling when powered by CarPC). I'll chime in later if its indeed low voltage on the USB.